Resizing hard drives in Parallels on Mac

Parallels is a very cool virtual machine system for Mac (and Windows and Linux). Particularly cool is the ability to resize the hard drive image you have for a given VM. But, the Parallels manual is not accurate on how to do this, or rather is missing some steps (maybe they don't intend for you to have to do this, but haven't finished this functionality?). A thread on their forum leads to the solution, but the thread is a bit jumbled and you need to put together the full solution. For ease, here's the step by step I used to make it work:

1. Shutdown Parallels


2. Run the "Image Tool" that comes with Parallels.


3. Resize the disk you want (it needs to be an "expandable" disk, but Parallels makes them this way by default. If yours is not for some reason, read their manual on how to convert it to one).


4. I did not bother making a backup of my image prior to this, but of course, standard cautions apply.


5. Now, what Image Tool actually does, is just to make the disk bigger, it doesn't actually affect the change on your virtual disk volume.


6. Go get the GPartEd LiveCD. You don't need to burn it to a CD.


7. Now, start up Parallels, and do two things for your virtual machine:
   
   


1. Change the boot order, so CDROM is first, and
   
   


2. In the CD options, change it to use a disk image, and then go browse to the GPartEd Live CD ISO you just downloaded.




8. Run the VM, which will boot into GPartEd. Accept all the default options.


9. Once GPartEd is running, select the initial partition, and click the Resize toolbar button. In the resulting dialog, drag it to fill the additional space, hit OK; then Apply the changes. Shutdown GPartEd.


10. Boot up your Parallels VM. If doing this for Windows, you'll see Windows do a chkdsk. Once booted, you'll see it say you have new devices and need to restart. This is fine, do so. Once it restarts and is back, you're good to go.